Zhengwen Li

This study investigated an efficient approach for extracting saponins from Panax japonicus using deep eutectic solvents (DES) coupled with ultrasound-assisted (UA) extraction, and compared its performance with the methanol extraction method. Twenty-six DES were screened, and choline chloride–urea was selected as the optimal solvent. The total extraction yield was evaluated based on the sum of the yields of chikusetsusaponin IVa (CS-IVa) and ginsenoside Ro (G-Ro). The extraction process was optimized using single-factor experiments combined with an orthogonal array design. Molecular dynamics (MD) simulation was applied to reveal the extraction mechanism at the molecular level. The results showed that the optimal conditions were as follows: a choline chloride-to-urea molar ratio of 1:3, a solid-to-liquid ratio of 1:50, a water content of 60%, an ultrasonic temperature of 40 °C, and an ultrasonic time of 60 min. Under these conditions, the total extraction yield of Panax japonicus saponins reached 7.4%, which was 13% higher than that obtained with the pharmacopeia methanol extraction method. MD simulation demonstrated that DES weakens intermolecular interactions among saponins through hydrogen bonds and van der Waals forces, promoting the dispersion of saponin aggregates and enabling efficient dissolution. Compared with CS-IVa, G-Ro displayed a more pronounced solvation effect, which was likely attributed to the difference in the number of polar sites in their molecular structures. The UA-DES extraction method established herein is green and efficient. It provides a practical reference for the industrial extraction of Panax japonicus saponins and a theoretical foundation for mechanistic studies on natural product extraction using DES.

Background: The senescence-associated hepatic gene set (SHGS) is critical in metabolic-dysfunction-associated steatotic liver disease (MASLD) progression. However, causal links between SHGS genes and liver diseases remain unclear. Methods: Mendelian randomization (MR) was used to explore causal relationships between SHGS genes and liver diseases. Immune infiltration of key genes was analyzed using the CIBERSORT algorithm with GEO database data, validated by single-cell RNA sequencing (scRNA-seq). Virtual docking assessed quercetin’s potential to modulate SHGS proteins and mitigate liver aging. Results: MR analysis identified elevated GBP2 expression as a risk factor for liver fibrosis (OR = 1.904, p = 0.028) but protective against cholangiocarcinoma (OR = 0.548, p = 0.001). Immune profiling and scRNA-seq revealed GBP2’s negative correlation with macrophages in fibrosis and positive correlations with T and NK cells in cholangiocarcinoma. Molecular docking suggested that quercetin indirectly suppresses GBP2 via IRF1, potentially attenuating liver aging. Conclusions: GBP2 might modulate hepatic fibrosis and cholangiocarcinoma. Quercetin may exert antifibrotic effects by indirectly modulating GBP2.

Quercetin, a dietary flavonoid, has demonstrated antioxidant, anti-inflammatory, and anti-tumor activities. Increasing evidence highlights that its metabolites contribute to these health benefits. This review summarizes current knowledge on the molecular mechanisms and therapeutic potential of quercetin and its metabolites in non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC), with a focus on redox modulation and microbiota interactions. Substantial preclinical evidence supports the protective effects of quercetin and its metabolites in NAFLD and HCC. However, clinical translation is hampered by poor bioavailability, potential redox–drug interactions, and incomplete understanding of the precise molecular mechanisms involved. Future research should prioritize further elucidating the molecular mechanisms, as they represent the foundation for the rational use of quercetin and metabolite-based derivatives in the prevention and treatment of liver-related diseases. In particular, strategies that direct the activity of these bioactive compounds to their desired sites of action—by exploiting differences between normal and cancer cells—warrant more in-depth investigation.

Aspergillus flavus is both an agricultural and clinical pathogen, notable for its ability to contaminate crops with aflatoxins and cause invasive aspergillosis. The increasing emergence of azole resistance in A. flavus poses a serious challenge to food safety and human health. Although mutations in ergosterol biosynthesis genes have been reported in resistant isolates, their functional contributions remain largely unvalidated. In this study, we investigated the role of the CYP51A Y119F mutation in azole resistance. Site-directed mutants were generated using PCR-based gene editing, and their susceptibility to antifungal agents was assessed through Clinical and Laboratory Standards Institute broth microdilution and agar diffusion assays. The Y119F mutation reduced susceptibility specifically to voriconazole and isavuconazole, while susceptibility to itraconazole and posaconazole remained unchanged. To explore the structural basis of this phenotype, molecular dynamics simulations were performed. The mutant protein exhibited greater fluctuations and reduced conformational stability compared to the wild-type enzyme. Tunnel analysis further indicated that the Y119F substitution caused narrowing and shortening of the main access tunnels to the heme-binding pocket, likely impairing azole access and binding. The combined biochemical and structural analyses suggest that Y119F represents a primary resistance-conferring mutation that modifies the structural dynamics of CYP51A.

Background: Renal fibrosis is a common pathological feature of all progressive chronic kidney disease (CKD). Eucommiae cortex (EC) is a valuable economic tree species endemic to China. The microbial fermentation of Chinese medicines can release their active ingredients as effectively as possible or produce new active ingredients with enhanced efficacy and reduced toxic side effects; Methods: The microbial fermentation of EC can produce pinoresinol (Pin) and dehydrodiconiferyl alcohol (DA). In this study, C57 BL/6 mice were fed a diet containing 0.2% adenine, resulting in a model of chronic kidney disease. The effects of EC and EC ferment (ECF) on CKD were explored by the exogenous supplementation of EC and ECF; Results: The results of the study showed that exogenous supplementation with EC and ECF suc-cessfully reduced creatinine and urea nitrogen levels, down-regulated the expression levels of TGF-β1, α-SMA, Smad3, and phospho-Smad3 in the TGF-β1/Smad signaling pathway, and ameliorated renal fibrosis; Conclusions: Both EC and ECF may have reno-protective effects and provide a reference for relevant clinical drug development.

Background: Quercetin, a dietary flavonoid and a widely used supplement, has hepatoprotective properties. Given its urate-lowering effects and epidemiological evidence linking elevated serum urate levels to liver cancer risk, we tested whether quercetin reduces liver cancer risk via modulation of urate levels by bioinformatics methods. Methods: We employed drug-target Mendelian randomization using genome-wide association study summary statistics from public databases (e.g., MRC-IEU) to assess genetic associations, and integrated these findings with GEO datasets (such as GSE138709 and GSE179443) and immune infiltration analyses using tools like xCell, TIMER. Results: Our analyses identified ABCG2-mediated urate elevation as a causal risk factor for hepatocellular carcinoma (OR = 1.001, p < 0.01), cholangiocarcinoma (OR = 3.424, p < 0.01), and liver fibrosis (OR = 2.528, p < 0.01). Single-cell transcriptomics revealed elevated ABCG2 expression in cholangiocarcinoma endothelial cells, while immune infiltration analysis showed significant associations between ABCG2 expression and both endothelial cell and macrophage infiltration. Survival analysis further indicated that ABCG2 was not associated with poor prognosis in cholangiocarcinoma or hepatocellular carcinoma. Conclusions: Considering quercetin’s multifaceted interactions with BCRP/ABCG2, our findings support its potential use as a preventive dietary supplement for hepatic diseases rather than as an adjunctive therapy for established liver cancer.

Background/Aim: Flavonoids are a group of polyphenols, abundantly present in our diet. Although, based on their chemoprotective effects, intake of flavonoids is associated with a high anticancer potential as evidenced in in vitro and in vivo models, the molecular mechanism is still elusive. This study explores the antiproliferative and cytotoxic effects of the semi-synthetic flavonoid MonoHER (7-mono-O-(β-hydroxyethyl)-rutoside) in vitro on cancer cells. Materials and Methods: HepG2 liver, MCF7 breast, and H1299 lung cancer cells were grown under ambient conditions with or without MonoHER exposure. CCK8 assay was used to assess cell viability. Apoptosis, JC-1, and mitochondrial mass were determined using flow cytometry and confocal analysis. The effects of monoHER on apoptosis proteins were detected by confocal microscopy analysis and Western blot. Results: It was found that MonoHER can reduce HepG2 cells’ and MCF7 cells’ viability, but not H1299 cells’, and induced apoptosis only in HepG2 cells. MonoHER has the potential to enhance the expression of caspase-9 and caspase-3, to damage mitochondria, and to provoke the release of cytochrome C from the mitochondria. Conclusion: MonoHER can inhibit cell growth and induce apoptosis especially in HepG2 human liver cancer cells by triggering the mitochondrial signal transduction pathway, leading to the release of cytochrome C in the cytoplasm and the subsequent activation of caspase-9 and caspase-3. Future research should further explore MonoHER’s mechanism of action, efficacy, and potential for clinical translation.

Small Heterodimer Partner (SHP; NR0B2) is an orphan receptor that acts as a transcriptional regulator, controlling various metabolic processes, and is a potential therapeutic target for cancer. Examining the correlation between the expression of NR0B2 and the risk of gastric diseases could open a new path for treatment and drug development. The Gene Expression Omnibus (GEO) database was utilized to explore NR0B2 gene expression profiles in gastric diseases. Co-expressed genes were identified through Weighted Correlation Network Analysis (WGCNA), and GO enrichment was performed to identify potential pathways. The Xcell method was employed to analyze immune infiltration relationships. To determine the potential causal relationship between NR0B2 expression and gastric diseases, we identified six single-nucleotide polymorphisms (SNPs) as a proxy for NR0B2 expression located within 100 kilobases of NR0B2 and which are associated with triglyceride homeostasis and performed drug-target Mendelian randomization (MR). Bioinformatics analysis revealed that NR0B2 expression levels were reduced in gastric cancer and increased in gastritis. GO analysis and Gene Set Enrichment Analysis (GSEA) showed that NR0B2 is widely involved in oxidation-related processes. Immune infiltration analyses found that NR0B2 was associated with Treg. Prognostic analyses showed that a low expression of NR0B2 is a risk factor for the poor prognoses of gastric cancer. MR analyses revealed that NR0B2 expression is associated with a risk of gastric diseases (NR0B2 vs. gastric cancer, p = 0.006, OR: 0.073, 95%CI: 0.011–0.478; NR0B2 vs. gastric ulcer, p = 0.03, OR: 0.991, 95%CI: 0.984–0.999; NR0B2 vs. other gastritis, p = 0.006, OR:3.82, 95%CI: 1.468–9.942). Our study confirms the causal relationship between the expression of NR0B2 and the risk of gastric diseases, and highlights its role in the progression of gastric cancer. The present study opens new avenues for exploring the potential of drugs that either activate or inhibit the NR0B2 receptor in the treatment of gastric diseases.

It has been reported that in an oxidative environment, the flavonoid 2R,3R-dihydroquercetin (2R,3R-DHQ) oxidizes into a product that rearranges to form quercetin. As quercetin is a very potent antioxidant, much better than 2R,3R-DHQ, this would be an intriguing form of targeting the antioxidant quercetin. The aim of the present study is to further elaborate on this targeting. We can confirm the previous observation that 2R,3R-DHQ is oxidized by horseradish peroxidase (HRP), with H₂O₂ as the oxidant. However, HPLC analysis revealed that no quercetin was formed, but instead an unstable oxidation product. The inclusion of glutathione (GSH) during the oxidation process resulted in the formation of a 2R,3R-DHQ-GSH adduct, as was identified using HPLC with IT-TOF/MS detection. GSH adducts appeared on the B-ring of the 2R,3R-DHQ quinone, indicating that during oxidation, the B-ring is oxidized from a catechol to form a quinone group. Ascorbate could reduce the quinone back to 2R,3R-DHQ. No 2S,3R-DHQ was detected after the reduction by ascorbate, indicating that a possible epimerization of 2R,3R-DHQ quinone to 2S,3R-DHQ quinone does not occur. The fact that no epimerization of the oxidized product of 2R,3R-DHQ is observed, and that GSH adducts the oxidized product of 2R,3R-DHQ on the B-ring, led us to conclude that the redox-modulating activity of 2R,3R-DHQ quinone resides in its B-ring. This could be confirmed by chemical calculation. Apparently, the administration of 2R,3R-DHQ in an oxidative environment does not result in ‘biotargeting’ quercetin.

Most studies on the antioxidant activity of flavonoids like Quercetin (Q) do not consider that it comprises a series of sequential reactions. Therefore, the present study examines how the redox energy flows through the molecule during Q’s antioxidant activity, by combining experimental data with quantum calculations. It appears that several main pathways are possible. Pivotal are subsequently: deprotonation of the 7-OH group; intramolecular hydrogen transfer from the 3-OH group to the 4-Oxygen atom; electron transfer leading to two conformers of the Q radical; deprotonation of the OH groups in the B-ring, leading to three different deprotonated Q radicals; and finally electron transfer of each deprotonated Q radical to form the corresponding quercetin quinones. The quinone in which the carbonyl groups are the most separated has the lowest energy content, and is the most abundant quinone. The pathways are also intertwined. The calculations show that Q can pick up redox energy at various sites of the molecule which explains Q’s ability to scavenge all sorts of reactive oxidizing species. In the described pathways, Q picked up, e.g., two hydroxyl radicals, which can be processed and softened by forming quercetin quinone.